Cement charger for dump truck



March 31, 1959,

JIH- NOBLE CEMENT CHARGER FOR DUMP TRUCK Filed Aug. 17, 1955 mmvroa JOHN H. NOBLE.

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United States Patent CEMENT CHARGER FOR DUMP TRUCK John H.'Noble, Pittsburgh, Pa., assignor to Dravo Corp0- ration, Pittsburgh, Pa., a corporation of Pennsylvania Application August 17, 1955, Serial No. 529,047

2 Claims. (Cl. 2.98--3) The present invention relates to an improved form of cement charger and distributor for compartmented aggregate carrying dump trucks.

It is now the general practice to use compartmented dump trucks for delivering bulk cement simultaneously with aggregate to be mixed into concrete at the construction site. These compartments are formed by mounting swinging gates transversely of the truck body in spaced relation longitudinally of the truck body. Containers for a measured quantity of cement, corresponding to the amount of aggregate in the compartment, are mounted on the gate for simultaneou discharge of the cement with the aggregate within the compartment. It has long been recognized that mixing of the concrete is facilitated where the cement and aggregate are partially mixed during the dumping operation. Many examples of cement chargers for this latter purpose are found in the prior art. Such prior art however has been found deficient to produce the desired results in a speedy and economical manner. In large construction work particularly, it has been found economically desirable to effect rapid discharge of successive compartments with a minimum of physical effort on the part of the truck driver and to automatically control the mixing of the cement and aggregate during the dumping operation.

One object of the invention is to provide a cement charger which is automatic in discharging the cement with the associated aggregate within the compartment.

Another object of the invention is to provide a cement charger which delivers the cement into the discharging aggregate from the compartment with an automatic and controlled mixing action.

" Another object of the invention is to provide a cement charger of simple but rugged construction, which is watertight and adapted for use with a plurality of truck body widths.

These and other objects will be made apparent as the specification proceeds and in the drawing forming a part thereof, wherein:

Fig. 1 shows in side elevation an aggregate dump truck equipped with the cement charger of the invention;

Fig. 2 shows a front elevation of the cement charger; and

Fig. 3 shows a side elevation of the cement charger and manner of mounting same on a compartment gate or fixed end wall of the truck.

Referring now in detail to the drawing, the dump truck 1 may be of any suitable form and provided with a substantially rectangular body 2 pivotally connected to the truck chassis 3 by any suitable means such as the pivotal connection 4. The truck is provided with a suitable powered body dumping means indicated generally by reference character 5. The body 1 is provided with gates 6 disposed transversely and spaced longitudinally of the body to provide a plurality of compartments 7. The usual pivotal rear end gate 8 is provided at the discharge end of the body. The body 1 is also provided with the 2,880,035 Patented Mar. 31, 1959 usual side walls 9, fixed front end wall 10 and floor 11. The gates 6 are pivotally mounted on the body side walls 9 and are provided with suitable locking mechanisms (not shown) for releasably retaining the gates in upright position as shown to the left of Fig. 1. The truck and body so far described are conventional, being well known in the art and commercialy available.

The cement charger comprises a front wall 12, top wall 13, side walls 14 connecting the front and top walls, a rear wall 15 connecting the side and top walls and a sloping bottom wall 16. The bottom edge of rear wall 15 is spaced above bottom wall 16 to provide a discharge opening 17. The discharge opening is closed by door 18 pivotally connected with wall 15 by hinges 19 secured to the member 20 extending longitudinally of and attached to the front wall. The top wall 13 has an open ing therein closed by the door 21, said door being pivotally connected to wall 12 by a suitable hinge 22 and is preferably provided with a flange 23 overlapping the wall 15. Suitable handles 24 may be secured to door 21 for raising and lowering the door. Secured to the rear wall 12 are two or more mounting brackets comprising a portion 25 secured to the wall 12, an outwardly extending flange portion 26 and a depending flange portion 27. The cement charger is mounted on the gate 6 by hooking the depending bracket flange over the top of the gate. The charger is held in fixed relation to the gate by means of bolts 28 passing through the charge rear wall 12, bracket portion 25, spacing block 29 and the gate 6. The gate 6 is shown as being formed of a metal plate having a top flange 30, however the gate may be formed of wood or other suitable material.

Referring now to Fig. 1 of the drawings, the truck body is shown as having a rear end gate 8, two releasable gates 6 and a fixed front end wall 10 forming three compartments for receiving aggregate. Cement chargers are mounted on each gate 6 and the end wall 10. The bottom of each cement charger (Figs. 2 and 3) is spaced above the floor 11 of the truck body a considerable distance permitting aggregate to flow around and beneath the charger, for a purpose hereinafter set forth. The truck body is prepared for loading by securing the gates 6 in upright position by the usual locking mechanisms (not shown) and securing the end gate 8 in closed position. Each of the compartments are first filled with aggregate so that the discharge doors 18 of each charger are held in closed position by the aggregate. The doors 21 in the top wall of the charger are then raised and the charger filled with the desired amount of cement. After filling, the doors 21 are lowered and the cement is retained in dry condition until discharged.

After the truck reaches the unloading point, the body is tilted as in Fig. l and the end gate 8 released to swing outwardly for unloading the adjacent end compartment. As the aggregate flows out of the compartment and away from the discharge door of the cement charger, the discharge door 18 swings outwardly and upwardly discharging the cement upon the discharging aggregate. After the cement is completely discharged from the charger, enough aggregate remains in the compartment, beneath and at the sides of the charger, to be deposited upon and cover the discharged cement. When it is desired to unload succeeding compartments in the truck body, the driver merely releases the latches on successive gates 6 and the discharging operation of aggregate and cement is repeated.

It has been found by extensive field tests that the charger as herein defined provides effective and controlled mixing of the discharging aggregate and cement. For example, a truck compartment of 34 cu. ft. aggregate capacity having a cement charger and distributor of 15 cu. ft. capacity provides an initial discharge of 4 or 5' cu. ft. of aggregate before the discharge door of the charger opens. Thereafter a ribbon of cement is discharged upon the aggregate moving out of the compartment until the cement is fully discharged. At this point about 4 or 5 cu. ft. of, aggregate remains beneath the charger and continues to discharge upon and substantially surround the discharged cement. In the tests referred to the aggregate and cement were discharged into a paver skip of a batch mixer used in paving operations. The skip is indicated in Fig. 1 by the reference character 31. The bottom of the discharge door 18 of the charger was spaced above the floor of the compartment varying distances between 16 and 20 inches. In each test, as indicated on Fig. 1, the cement charger and distributor were mounted upon a fixed wall of the compartment so that the aggregate within the compartment flowed away from said wall in discharging from the compartment. Thus the aggregate within the compartment retained the discharge door 18 closed until after the discharging operation commenced. In those cases where the charger was mounted upon a swinging wall 6, the wall was locked in fixed relation to the compartment floor during discharging of cement and aggregate from the compartment and unlocked to discharge aggregate and cement from the compartment behind the respective gates 6.

Having thus described the invention many obvious modifications therein will suggest themselves to those skilled in the art without departing from the spirit of the invention and it is to be understood that the exact details disclosed herein were for purposes of illustration and not limitation except as made necessary by the scope of the appended claims.

Iclaim:

1. In a compartmented tilting body aggregate dump truck, in combination, a pair of transversely disposed longitudinally spaced walls on said body defining a com-v partment, one of said wallsbeing pivotally supported on the body for swinging upwardly during tilting of the body for discharge of aggregate behind the swinging wall, a cement charging and distributing enclosure mounted in fixed relation on the other of said walls and within the compartment, said enclosure having a fixed bottom wall extending away from the supporting wall and disposed in vertically spaced relation to the floor of said compartment, a pivotally mounted upwardly swinging door extending upwardly from the outer edge of said enclosure bottom wall and forming a part of the front wall of the enclosure, said enclosure swinging door being held closed by pressure of aggregate within the compartment and opening by gravity for discharge of the cement upon the adjacent discharging aggregate during tilting of the body in discharging aggregate from the compartment.

2. The combination as defined in claim 1 wherein the enclosure bottom wall slopes outwardly and downwardly from the enclosure supporting compartment wall with the lower most portion of said bottom wall in sufiicient spaced relation to the floor of the compartment for reception of aggregate between the bottom and adjacent compartment floor, and the side walls of the enclosure are in spaced relation to the compartment body side walls forming pockets for reception of aggregate placed in the compartment.

References Cited in the file of this patent UNITED STATES PATENTS 1,533,419 Hug Apr. 14, 1925 1,624,376 Venable Apr. 12, 1927 1,867,699 Heil July 19, 1932 1,924,927 Harm et al. Aug. 29, 1933 

